Printable devices have been attracting considerable interest because of their application to flexible large-area devices in low cost printable electronics. In order to fabricate such devices, it is necessary to discover a passivation film and develop an efficient process for its preparation. We have previously reported that silicone oxide film is obtained with high density by UV irradiation to silazane compound film at low temperature [1]. The silicon oxide film has electric resistivity more than 10−15 Ωcm and electric strength more than 7 MV/cm. In order to apply the film to passivation layer in printable device, in this paper, preparation of nano-composite film with silicon oxide and clay mineral was investigated.